On Sun, 25 Mar 2018 12:24:24 +0100, Andy Burns
wrote:

Harry Bloomfield wrote:

with no working boiler there is no easy way to work out which is the
flow, which is the return at the rads


Some TRVs (e.g. Myson 2-way) are marked with a double-headed arrow to
indicate they can be fitted either way round, maybe yours are too?

That said, I still try to fit them so it's flowing in via the TRV, just
in case it helps cut down on annoying whistling.

Oddly enough after balancing my system, I noticed this and I still
have the original valves fitted.

It isn't loud and as I have the TRV's to fit I didn't bother doing
anything.

Is this common, with a simple solution?

I assume its turbulence, but can't be bothered having another tweaking
session.

I wouldn't like to think that the TRV's are going to open up another
day or so of tweaking or problem solving:-(

AB





Can you tell by which end of the rads have the lock-shield valve being
the return, I suppose that's only a convention, no guarantee.